How to teach a van to drive: an undergraduate perspective on the 2005 DARPA Grand Challenge

This paper describes how a team of undergraduate volunteers from California Institute of Technology (Caltech) developed a robotic vehicle that can navigate completely autonomously through the Mojave Desert. Called Alice, the vehicle was Caltech's entry to the 2005 DARPA Grand Challenge which aimed to generate the technology needed to build and program an unmanned ground vehicle through 130 miles of difficult terrain completely autonomously in under ten hours. Although Alice failed to win the competition, she did succeed in her original purpose of teaching a new generation of students about engineering, how to apply theory to the real world, how to debug and deal with shortcomings and schedules, and most importantly, how to work as a team on a complex problem

The death road and the soul calling in Zilu-jing, or Sutra of indicating route, of the Yi in China : A study on the discourse of ancestral migration route with special reference to its relations with ethnic identity making

The Yi people in China conduct a magnificent funeral for the dead in which the Bi-mo, or the priest, recites Zilu-jing. Throughthis supra they see off the soul back along the believed ancestral migration route to Zizipow, their place of origin. The teaching ofZilu-jing is essentially to guide the souls of the dead, but at the same time it induces the spirits of the living people attending thefuneral too to escort the souls of the dead to their place of origin, where the spirits of the living people part from the souls of thedead and then are brought back to their place of living Through this experience the people of the Yi vividly learn their ethnicmigration history by retrieving their ancestors migration route recalled in Zilu-jin.All the versions of Zilu-jing handed down invarious places refer to Zizipow, Apudumu the Founder, and the ethnic migration route of the six ancestors.It means that the con-tents of Zilu-jing constitute a very significant part in making the ethnic identity of the Yi, though they have been dispersed to dateand thus formed no durable unified government

Connect and Conquer: Why teachers should help disabled students connect with resources

No abstract availabl

First-Order Systems Least-Squares Finite Element Methods and Nested Iteration for Electromagnetic Two-Fluid Kinetic-Based Plasma Models

Efforts are currently being directed towards a fully implicit, electromagnetic, JFNK-based solver, motivating the necessity of developing a fluid-based, electromagnetic, preconditioning strategy [15]. The two-fluid plasma (TFP) model is an ideal approximation to the kinetic Jacobian. The TFP model couples both an ion and an electron fluid with Maxwell’s equations. The fluid equations consist of the conservation of momentum and number density. A Darwin approximation of Maxwell is used to eliminate light waves from the model in order to facilitate coupling to non-relativistic particle models. We analyze the TFP-Darwin system in the context of a stand-alone solver with consideration of preconditioning a kinetic-JFNK approach. The TFP-Darwin system is addressed numerically by use of nested iteration (NI) and a First-Order Systems Least Squares (FOSLS) discretization. An important goal of NI is to produce an approximation that is within the basis of attraction for Newton’s method on a relatively coarse mesh and, thus, on all subsequent meshes. After scaling and modification, the TFP-Darwin model yields a nonlinear, first-order system of equations whose Fréchet derivative is shown to be uniformly H1-elliptic in a neighborhood of the exact solution. H1 ellipticity yields optimal finite element performance and linear systems amenable to solution with Algebraic Multigrid (AMG). To efficiently focus computational resources, an adaptive mesh refinement scheme, based on the accuracy per computational cost, is leveraged. Numerical tests demonstrate the efficacy of the approach, yielding an approximate solution within discretization error in a relatively small number of computational work units

Parcels: a Fast and Feature-Rich Binary Deployment Technology

While development of a software system is important, it is also very important to have suitable mechanisms for actually deploying code. Current state-of-the-art deployment approaches force the developer to structure the code in such a way that deployment is possible, thereby severely inhibiting reuse and comprehensibility of the system. This paper presents parcels, an atomic deployment mechanism for objects and source code that supports shape changing of classes, method addition, method replacement, and partial loading. The key to making this deployment mechanism feasible and fast is a pickling algorithm that allows the unpickling to be done iteratively instead of with a recursive descent parser. Parcels were developed for VisualWorks Smalltalk, and have been the default deployment mechanism the past years for thousands of customers